EP0869164A1 - Lubricant comprising sulfur-containing phtalocyanines or their metal complexes - Google Patents

Abstract

Lubricant contains one or more compounds of formula (I) (where, X = Mg, Ca, Zn, Cu, Ni, Co or 2H atoms; R1-R16 = H, Cl, F, OH, SH, Rx, ORx or SRx; Rx = 1-18C alk(en)yl in which one or up to 4 neighbouring CH2 groups can be substd. by O or S and by OH or halogen, an unsubstd. or with one or two halogen atoms or one or up to 3 alkyl groups with 1-9C atoms, in which a CH2 group can be replaced by O, substd. phenyl or cyclohexyl, an unsubstd. or with one or two halogen atoms or one or up to 3 alkyl groups with 1-9C atoms, in which each CH2 group can be replaced by O or S, substd. benzyl or cyclohexyl-methyl, 2-benzothiazolyl or naphthyl, with the proviso that at least four of R1 to R16 are SRx).

Description

To reduce wear and energy loss due to friction As is well known, machine bearings and gearboxes are provided with a lubricant which during of the company as complete a separation as possible of those moving against each other Solid body allows. The lubricants can be found in lubricants and greases be divided.

Mineral oils extracted from petroleum are synthetic as conventional lubricants Oils, such as polyalkylene glycols, ester oils or phosphoric acid esters, and silicone oils in use (see overview in Ullmann's Encyclical of Chemical Engineering, 4th Edition vol. 20). Mesogenic liquids are also known, i.e. thermotropic liquid crystalline Liquids that form phases in the lubricating gap from a low-viscosity can transition into a highly viscous phase and vice versa (US.5,160,451; Höhn et al., Tribology Conference Göttingen 1996, entry No. 13). General calls one mesogen a liquid when it is under arbitrary conditions (Pressure, temperature, shear, surface interactions) one or more can form liquid crystalline phases. The relationship between chemical Structure and arrangement of the molecules in such phases as well as the temperature range, in which such phases can occur is known (e.g. H. Kelker, R. Hatz, Handbook of Liquid Crystals, Verlag Chemie, Weinheim 1980; C. Destrade et al., Mol. Cryst. Liq. Cryst. Vol. 106, 121 (1984)). Lubrication is also widespread Greases. These consist of a lubricating fluid and a fine one in it Form dispersed solid, the so-called thickener, which is based on the tribological Properties has little influence and primarily the function of a Has storage for the lubricant. In addition, very low viscosity can also occur organic substances, such as fuels for gasoline engines (petrol) and diesel engines (Diesel fuel) can be understood as a lubricant, which is due to the known influence of fuel on the wear of nozzle needles of fuel injectors becomes clear. Also solutions and emulsions of organic liquids in Water serve as a lubricant, especially as a so-called cooling lubricant in the cutting deformation of metal workpieces. This coolant are included in the present invention, provided that compounds of formula I (see below) in the organic phase of the emulsion are dissolved.

The one in a friction pair - these are generally separated by a lubrication gap, mutually movable solid bodies - occurring energy losses and signs of wear depend in a complex way on the material of the machine element itself, the properties of the lubricating oil, such as its viscosity and its interactions with the material, as well as the pressure and speed ratios from. Closed support films, such as those in hydrodynamic, are cheap Range of plain bearings or in the elastohydrodynamic range of Rolling bearings occur. High friction losses - and generally with them correlating signs of wear - occur especially in plain bearings with so-called Limit and mixed friction (cf. VDI reports 680, The oil as a construction element, VDI publishing house, Düsseldorf 1988).

So-called EP (Extreme Pressure) and AW (Anti Wear) additives (see Ullmann), the protective layers can form between the bearing parts. Organic are particularly preferred Sulfur and phosphorus compounds. In particular, for steel-steel friction pairings Zinc dialkyl dithiophosphate cheap. The effectiveness of an additive depends very much on the chemical structure of the components of the lubricant. Known are also additives of metal complexes of phthalocyanine. These are in suspended form in oils (DE 3230593) or as additives for aqueous cutting oils (E. V. Berezina et al., Proc. Tribology - Solving Friction and Wear Problems, Esslingen 1996, 1231) used; they are in nonpolar organic liquids like the ones Commonly known lubricating oils are insoluble. The well-known lubricants are in need of improvement because of the contact between the solids in one Frictional losses due to machine bearings can only be avoided inadequately. In particular, lubricants based on mesogenic liquids are in need of improvement, because the known additives are not mesogenic and therefore they like known other non-mesogenic compounds the temperature range, in which can occur in liquid-crystalline phases.

worin

X

für ein Metall ausgewählt aus Mg, Ca, Zn, Cu, Ni, Co oder 2 Wasserstoffatome und

R1 bis R16

jeweils unabhängig voneinander für H, Cl, F, -OH, -SH, -Rx, -ORx und -SRx steht, wobei Rx ein organischer Rest mit 1 bis 18 C-Atomen ist, der einen Alkyl- oder Alkenylrest, worin auch eine oder bis zu 4 nichtbenachbarte CH₂-Gruppen durch -O-, -S-, substituiert sein können, und der auch ein- oder mehrfach durch -OH oder Halogen substituiert sein kann, einen unsubstituierten oder mit einem oder zwei Halogenatomen oder einer oder bis zu 3 Alkylgruppen mit 1 bis 9 C-Atomen, in denen jeweils eine CH₂-Gruppe durch O ersetzt sein kann, substituierten Phenyl- oder Cyclohexylrest, einen unsubstituierten oder mit einem oder zwei Halogenatomen oder einer oder bis zu 3 Alkylgruppen mit 1 bis 9 C-Atomen, in denen jeweils eine CH₂-Gruppe durch O oder S ersetzt sein kann, substituierten Benzyl- oder Cyclohexylmethylrest, einen 2-Benzothiazolylrest oder einen Naphthylrest bedeutet, mit der Maßgabe, daß mindestens 4 der Reste R1 bis R16 -SRx sind.

The object of the invention was to find a lubricant which enables particularly low friction losses in friction pairings. The object is achieved by providing a lubricant containing one or more compounds of the general formula I.

wherein

X

for a metal selected from Mg, Ca, Zn, Cu, Ni, Co or 2 hydrogen atoms and

R1 to R16

each independently represents H, Cl, F, -OH, -SH, -Rx, -ORx and -SRx, where Rx is an organic radical having 1 to 18 carbon atoms, which is an alkyl or alkenyl radical, in which also a or up to 4 non-adjacent CH ₂ groups can be substituted by -O-, -S-, and which can also be substituted one or more times by -OH or halogen, an unsubstituted or with one or two halogen atoms or one or bis to 3 alkyl groups with 1 to 9 C atoms, in each of which one CH ₂ group can be replaced by O, substituted phenyl or cyclohexyl radical, an unsubstituted or with one or two halogen atoms or one or up to 3 alkyl groups with 1 to 9 C atoms, in each of which a CH ₂ group can be replaced by O or S, means substituted benzyl or cyclohexylmethyl radical, a 2-benzothiazolyl radical or a naphthyl radical, with the proviso that at least 4 of the radicals are R1 to R16 -SRx .

It has surprisingly been found that the lubricant according to the invention allows particularly low friction losses in friction pairings.

The compounds of the formula I comprise the preferred sub-formulas Ia to Ic:

In the compounds of formula I, Rx each independently preferably an alkyl group with 1 to 18 carbon atoms, unbranched Alkyl groups with 4 to 12 carbon atoms are particularly preferred. Then they mean Butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl and dodecyl. Also preferred is the meaning of Rx as a group that is a substituted or unsubstituted Contains phenyl or cyclohexyl group. Here are the meanings of Rx particularly preferred as unsubstituted phenyl group and as cyclohexylmethyl group. In addition, the condensed aromatic residues are 2-naphthyl and 2-benzothiazolyl prefers.

The molecules of the compounds of formula I contain at least 4 sulfur atoms. The substituents H, Cl, F, -SH, -OH, -Rx, and -ORx are suitable for the at most twelve of the substituents R ₁ to R ₁₆ , which cannot mean -SRx. H, Cl and F are preferred.

In formula I for X, the metal atoms Mg, Ca, Zn, Cu and Ni and two hydrogen atoms stand. The meanings as two hydrogen atoms, Cu, are preferred as well as Zn and Ni.

The compounds of the formula I are prepared by methods known per se, as in the literature (e.g. in standard works such as Houben-Weyl, Methods of Organic Chemistry, Georg-Thieme-Verlag, Stuttgart; C. C. Leznoff, A. B. P. Lever, Editors, Phthalocyanines, VCH, New York 1989) are described under Reaction conditions that are known and suitable for the reactions mentioned are.

The starting materials are substituted phthalic anhydrides, phthalonitriles and phthalic acids. The ring formation takes place in the presence of metals, metal salts or metal oxides in high-boiling solvents. Alkali metal hydroxides are also used to prepare the metal-free phthalocyanines of the formula I (X = 2 hydrogen atoms). The metal-free phthalocyanines are released from the initially formed dialkali salts by reaction with acids. If a mixture of differently substituted phthalonitriles is used in the ring formation reaction, a mixture of compounds of the formula I is obtained. In this way, a high total concentration of compounds of the formula I in the lubricant according to the invention can be ensured even at low temperatures without crystallizing them out Connections should be feared. For example, if a mixture of 4,5-bis [octylthio] phthalonitrile and 4,5-bis [cyclohexylmethylthio] phthalonitrile is used in a manner known per se with a strong organic base, such as DBU (see Example 1), in one polar solvents, such as dimethyl sulfoxide, um, a mixture of the compounds is obtained

Compounds of the formula Ia are preferably starting from 4,5-dichlorophthalonitrile, over the 4,5-dithio-phthaloyl dinitriles (by reaction with thiols or Alkali thiolates) prepared by well-known ring closure reactions (A.G. Gurek, Ö. Bekaroglu, J. Chem. Soc. Dalton Trans. 1419 (1994)). The manufacture of the Hexadecakis [alkylthio] phthalocyanine and other compounds of formula Ic is in similarly - albeit with significantly poorer yields - starting from the 3,4,5,6-tetrachlorophthalodinitriles via those obtainable by nucleophilic substitution Thioether possible. An advantageous preparation of compounds of the formula I is by reaction of commercially available chlorine and fluorophthalocyanines or their Metal complexes with alkali thiolates in polar aprotic solvents and subsequent hydrolysis. Depending on the reaction conditions, more or less Chlorine atoms replaced by -SRx. So arise at 120 ° C in Tetraethylene glycol dimethyl ether with sodium octyl thiolate mainly compounds of formula I with 12 to 16 -SRx groups during the reaction at room temperature with alkylthiols in dimethyl sulfoxide in the presence of potassium carbonate compounds are obtained, the empirical formulas of which are based on the structure of the formula Ib applies.

4-thiol-phthalonitriles and sulfur-free phthalonitriles and the corresponding phthalic acids or phthalic anhydrides can also be used in the ring-forming reaction. Such sulfur-free compounds are, for example, phthalonitrile, 4,5-dichlorophthalodinitrile or 3,4,5,6-tetrachlorophthalodinitrile. Thus, in the reaction of 4,5-bis [octadecylthio] phthalonitrile with phthalonitrile under the above reaction conditions (Gurek), a mixture is formed which includes the following compounds of the formula I.

The lubricant according to the invention is produced by stirring in the compounds I at room temperature in organic liquids that work as a lubricant are known, e.g. Ester oils, mineral oils, polyethylene glycols (see Ullmann). Within In the present invention, these organic liquids also include mesogenic Compounds and mixtures of mesogenic compounds as well Mixtures of mesogenic and non-mesogenic compounds, also fuels for Otto and diesel engines. The concentrations of compounds Ia and Ib in the Lubricant is preferably used when lubricating slide and roller bearings in the range of 0.1 to 10%. The lubricant can also up to 100% consist of compounds of the formula I, especially when it comes to low-friction Separation of workpieces made of sintered metal from the shaping tool is used. For this purpose, it is added to the metal powder to be sintered. In which the relevant process, which normally takes place at> 150 ° C, is Lubricant liquid or liquid crystalline. The concentration is in fuels Compounds of the formulas I preferably below 0.1%.

The lubricant according to the invention can in addition to one or more compounds of formula I also contain other conventional compounds. This can include Antioxidants, such as derivatives of 2,6-di-tert-butylphenol, high-pressure additives such as zinc dialkyl dithiophosphates, Friction reducers, light stabilizers, emulsifiers or demulsifiers or antifoam.

All components in these lubricants are in molecularly dispersed form. By incorporating thickeners which are not present in the form of a molecule, a lubricating grease which is also covered by the invention can be produced therefrom. Particularly suitable thickeners are lithium 12-hydroxy stearate and powder made of polytetrafluoroethylene (eg microteflon powder 5µ, Dr. Tillwich GmbH, Horb). Within the scope of the present inventions, polymers serving for the formation of gels, such as so-called side chain polymers (H. Ringsdorf et al., Angew. Chem. 101 , 934 (1989) and literature cited therein), as well as inorganic solid additives such as molybdenum disulfide , Calcium phosphate, zinc diphosphate or graphite, are among the thickeners. An inventive grease can contain up to 35% of such thickeners. The distinction between molecularly disperse and non-molecularly disperse substances can be made by an ultracentrifugation (for example with the Beckmann L8-M ultracentrifuge at a centrifugal acceleration between 7x10 ⁵ and 6x10 ⁵ m / s ² at 25 ° C., 10 min) in a manner known per se.

worin mindestens 3 der Substituenten X₁ bis X₆ einen nichtcyclischen organischen Rest mit jeweils 6 bis 18 C-Atomen bedeuten,
der Formel III

worin mindestens 3 der Substituenten Y₁ bis Y₆ einen nichtcyclischen organischen Rest mit 6 bis 18 C-Atomen bedeuten und der Formel IV

worin mindestens 3 der Substituenten Z₁ bis Z₆ einen nichtcyclischen organischen Rest mit 6 bis 18 C-Atomen bedeuten.It has been found that the lubricants according to the invention, which form a thermotropically liquid-crystalline phase at normal pressure at a temperature above -40 ° C., enable particularly low friction losses in friction pairings. This is possibly due to a favorable alignment of the molecules of the compounds of the formula I. The temperature ranges in which liquid-crystalline phases can exist can also be shifted upward by adding the compounds of the formula I to mesogenic liquids. Liquid-crystalline phases are divided into calamitic phases, which are formed by molecules with an elongated shape, and discotic phases, which are formed by plate-shaped molecules (see Destrade). According to the general laws of thermodynamics, the phase affiliation depends on pressure and temperature, on two variables, the measurements of which are very difficult at the critical, microscopic points of a machine bearing. Interactions of the lubricants according to the invention on the surface of the bearing materials may also favor favorable molecular orientations which lead to low friction losses. Lubricants which can form discotic phases are preferred. Such phases can be formed from pure compounds of formula I and mixtures of several compounds of formula I. In addition to the compounds of the formulas I, such lubricants capable of forming discotic phases can also contain other compounds. Preferred components here are compounds of the formula II

in which at least 3 of the substituents X ₁ to X _{6 represent} a noncyclic organic radical each having 6 to 18 carbon atoms,
of formula III

wherein at least 3 of the substituents Y ₁ to Y _{6 represent} a noncyclic organic radical having 6 to 18 carbon atoms and the formula IV

in which at least 3 of the substituents Z ₁ to Z _{6 represent} a noncyclic organic radical having 6 to 18 carbon atoms.

For X ₁ to X ₆ , Y ₁ to Y ₆ and Z ₁ to Z ₆ , the preferred meanings are alkyl, alkylthio, alkoxy, alkoxycarbonyl, acyloxy, H, Cl, SH and OH.

Such discogenic lubricants are encompassed by the present invention, their Total content of compounds of formulas II, III and IV is between 99.9 and 0%. It is preferably between 99.8% and 10%. Among the compounds II to IV are the components of the lubricant according to the invention Formula II preferred.

It was also found that general friction pairings also with those according to the invention Lubricants that are above -40 ° C under normal pressure Thermotropic liquid crystalline phases can form favorable friction losses in friction pairings exhibit. In particular, plain bearings and roller bearings show when in use the lubricant according to the invention has lower friction losses than when used of lubricants which do not contain one or more compounds of the formula I contain. The lubricants according to the invention can advantageously be used as motor oils Lubrication of the sliding pairs in the piston groups can be used. Likewise Their use as fuels for petrol and diesel engines with one is advantageous wear of the nozzle needles of the injection nozzles due to little friction, for cold forming of metals (deep drawing of sheet metal) and for reduction the friction of workpieces made of sintered metal when removed from the sintered mold.

The energy losses that occur in a friction pair depend in a complex manner on the material of the solids involved, the properties of the lubricants and the pressure and speed conditions. It is common practice to specify the coefficient of friction µ as a measure of the friction and thus of the friction losses. µ is defined as the quotient of F _R (frictional force) and F _N (normal force = force with which the solid bodies are pressed against each other). µ = F R / F N

To the ability of various lubricants, the friction losses in friction pairings To reduce, to be able to compare, values for µ measured under conditions that are as close as possible to the conditions of use come. A widely used method is the so-called SRV test (Optimol Instruments Prüftechnik GmbH, Munich; DIN 51834, part 1 and 2), which is mainly in the area of Boundary and mixed friction is meaningful.

In addition to organic compounds, the lubricants according to the invention contain the can be used as lubricating oils, one or more compounds of formula I. The lubricant can be at room temperature and normal pressure (atmospheric pressure) in the isotropic or a thermotropic liquid crystalline Phase (nematic, smectic, diskoid-nematic or columnar-discotic, see Kelker and Destrade). In addition, a gel-like condition, for which purpose lyotropic liquid-crystalline phases are also to be counted.

The compounds of formula I can be obtained from the lubricant by well known means Separation methods isolated and their chemical structural formula with general known analytical and spectroscopic methods can be determined. Cut expediently by means of the so-called HPLC (High Performance Liquid Chromatography) with organic flow agents and a stationary phase made of silica gel particles (e.g. LiChrosorb, Merck KGaA, Darmstadt). Come as a spectroscopic method Mass Spectroscopic Methods (H.Budzikiewicz, Mass Spectroscopy 3. Edition, Verlag Chemie Weinheim 1992) and the known methods of nuclear magnetic resonance spectroscopy in question. In addition, elementary analysis is used to elucidate the structure and absorption spectroscopy is helpful.

The following examples are intended to illustrate the inventions without limiting them. Above and below are all temperatures in ° C and all content in mass percent.

example 1

44.2 g of octantinol and 29.6 g of 4,5-dichlorophthalodinitrile are dissolved in 175 ml of absolute dimethyl sulfoxide under nitrogen. 75 g of finely ground potassium carbonate are then added in portions over the course of 2 hours, and the reaction mixture is stirred under nitrogen for 16 hours at room temperature. After the addition of 500 ml of water is extracted 4 times with 100 ml of chloroform. The combined organic phases are washed successively with 100 ml of 5% sodium carbonate solution and then twice with water. After drying with sodium sulfate and distilling off the chloroform, 61.2 g of an oily residue remain. This is dissolved in 1200 ml of hot ethanol. The crystals formed from this solution at room temperature are filtered off with suction and dried in vacuo: 47.4 g of 4,5-bis [octylthio] phthalonitrile, melting point 59 ° C.
40 g of this are dissolved in 3 l of pentanol and 15 g of 1,8-diazabicyclo [5.4.0] undec-7-ene (DBU) are added under nitrogen and the solution is heated under reflux for 72 h. After cooling to room temperature and leaving to stand for 24 hours, the dark green powder is filtered off and washed 3 times with 200 ml of hot ethanol. After drying, 13.7 g of 2,3,9,10,16,17,23,24-octakis [octylthio] -29H, 31H-phthalocyanine, absorption maximum (in dichloromethane) at 699 nm, extraction coefficient 6.72x10 ⁴ 1000 cm ² / mol.

A lubricant made by dissolving 10 mg of this compound in 10 g of one Diesel fuel (EN 590) is tested for its friction behavior in an SRV test bench from Optimol Instruments Prüftechnik GmbH.

In the cylinder-to-plate arrangement, the cylinder is operated at a controlled frequency, Normal force and regulated stroke horizontally under 10 ° to the stroke direction over the plate emotional. The apparatus is coupled to a computer that records the measurement data takes over. Depending on the time, all settings can be made on this computer Parameters (force, frequency, stroke, temperature) and the coefficient of friction (coefficient of friction) and the wear and tear are spent.

Cylinders and plates made of 100Cr6 (test specimen from Optimol) are used for the tests. The cylinder has a polished surface, the plates are lapped with an average roughness R _z of 0.45 µm to 0.65 µm. The cylinder has a length of 22 mm and a diameter of 15 mm; the plate has a diameter of 24 mm and a height of 7.9 mm. The cylinder is ground slightly towards the end faces so that there is a contact length (line contact) of approx. 15 mm ± 0.5 mm. Before the test specimens are used, they are cleaned twice in 5 minutes in acetone in an ultrasonic bath. Between the individual experiments, the test specimens are cleaned with acetone if used several times.

After cleaning the specimen and installing it in the testing machine, 2 to 3 Drop of lubricant applied to the sample surface of the plate. After hiring the test parameters (10 N, 50 Hz, 1 mm, RT, 2 h) are the samples under Test load brought into contact and the test started. There was no running-in period a reduced burden instead. The rel. Humidity during the experiments ranged between 30% and 45% (laboratory atmosphere). The temperature of the samples or the lubricant resulted from the resulting frictional heat and moved between 21 ° C and 28 ° C. The average speed from the above Parameters result in 0.1 m / s, the glide path covered after 2 hours of testing is 720 m.

After this time, a coefficient of friction µ of 0.09 is measured. A comparison attempt with the pure diesel oil results in a µ of 0.17 under otherwise identical conditions.

Example 2

Ausbeute: 6,0 g 2,3,9,10,16,17,23,24-Octakis[octylthio]-29H,31H-phthalocyanin-Zink-Komplex

Absorbtionsmaximum (in Dichlormethan) 711 nm,

Extinktionskoeffizient 7,67x10⁴ 1000 cm²/mol.

10 g of the octakis [octylthio] phthalocyanine from Example 1 are combined with 1.5 g of anhydrous zinc acetate and 30 ml of quinone and stirred at 200 ° C. under nitrogen for 6 hours using a magnetic stirrer. The reaction mixture, cooled to room temperature, is mixed with 30 ml of ethanol. The dark green crystals are filtered off and washed with 200 ml of hot ethanol. The precipitate which has precipitated out of the combined filtrates after 24 h is filtered off and combined with the first precipitate. The combined crystals are boiled up with 100 ml of ethanol, filtered off and dried:

Yield: 6.0 g 2,3,9,10,16,17,23,24-octakis [octylthio] -29H, 31H-phthalocyanine-zinc complex

Absorption maximum (in dichloromethane) 711 nm,

Extinction coefficient 7.67x10 ⁴ 1000 cm ² / mol.

In the test bench described in Example 1 under the conditions specified there gives a lubricant made from 30 mg of this zinc compound and 1 g of the commercial lubricating oil (mineral oil based) Tellus 100 (Shell AG) has a coefficient of friction µ of 0.12. Under the same conditions, Tellus 100 gives a coefficient of friction of 0.19.

Example 3

5.0 g of commercial hexadecachlor-29H, 31H-phthahlocyanine, 20.0 g of octanethiol, 20.2 g of anhydrous potassium carbonate and 50 ml of absolute dimethyl sulfoxide are combined in a glass flask under nitrogen at room temperature for 14 days with a Magnetic stirrer stirred. The contents of the flask are then stirred with 150 ml of water and the suspension formed 3 times with 100 ml of dichloromethane. The United organic phases are washed 6 times with 50 ml of water, then with sodium sulfate dried and the dichloromethane distilled off. The backlog is in Oil pump vacuum (<0.1 mbar) freed of excess octanethiol at 100 ° C. Of the now remaining solid residue is in a mixture of 20 ml of petroleum spirit and 10 ml dichloromethane dissolved and the solution over a short chromatographic Column (100 g silica gel, petroleum spirit / dichloromethane 2: 1) separated. The main fraction of 7.8 g contains octachlor-octakis [octylthio] phthalocyanine according to the FD mass spectrum among other compounds encompassed by formula I. are. By stirring 50 mg of this mixture with 1 g of hexakis [octylthio] benzene a lubricant is made. A drop of this is placed between two glass plates Chilled to -40 ° C. Under the polarizing microscope, a discotic liquid crystalline Phase observed that changes to the isotropic phase when heated. The friction behavior of the lubricant is the same as that mentioned in Example 1 Test bench examined under the conditions mentioned there. There is a coefficient of friction from 0.07. The one with pure hexakis [octylthio] benzene under the same Conditions measured coefficient of friction is 0.12.

Example 4

In the manner shown in Example 1, a mixture in a molar ratio 1: 1: 1 of 4,5-bis [octylthio] phthalonitrile, 4,5-bis [dodecylthio] phthalonitrile and 4,5-bis [butylthio] phthalonitrile Mixture made from 2,3,9,10,16,17,23,24-octakis [alkylthio] -29H, 31H-phthalocyanines. Analogously to Example 2, a mixture of the corresponding nickel complexes is produced from this by reaction with anhydrous NiCl ₂ . A lubricant (grease) prepared from 2 g of this, 2 g of lithium 12-hydroxy stearate and 6 g of Pentakis [octylthio] benzene in a generally known manner by briefly heating to 220 ° C. is used to lubricate a worm gear (F. Morat KG, Eisenbach; gear ratio 38: 1, worm A31Ü38, worm wheel A31Ü38B; 3000 revolutions / min) was used. The gear running without load has a temperature about 10 ° C lower after 10 min running time than the same gear when lubricated with a grease made from 8 g Pentakis [octylthio] benzene and 2 g lithium 12-hydroxy-stearate.

Claims (11)

Lubricants containing one or more compounds of the general formula I.

wherein

X

for a metal selected from Mg, Ca, Zn, Cu, Ni, Co or 2 hydrogen atoms and

R1 to R16

each independently represents H, Cl, F, -OH, -SH, -Rx, -ORx and -SRx, where Rx is an organic radical having 1 to 18 carbon atoms, which is an alkyl or alkenyl radical, in which also a or up to 4 non-adjacent CH ₂ groups can be substituted by -O-, -S-, and which can also be substituted one or more times by -OH or halogen, an unsubstituted or with one or two halogen atoms or one or bis to 3 alkyl groups with 1 to 9 C atoms, in each of which one CH ₂ group can be replaced by O, substituted phenyl or cyclohexyl radical, an unsubstituted or with one or two halogen atoms or one or up to 3 alkyl groups with 1 to 9 C atoms, in each of which a CH ₂ group can be replaced by O or S, means substituted benzyl or cyclohexylmethyl radical, a 2-benzothiazolyl radical or a naphthyl radical, with the proviso that at least 4 of the radicals are R1 to R16 -SRx .

Lubricant according to claim 1, characterized in that R1, R4, R5, R8, R9, R12, R13 and R16 each independently of one another H or Cl and R2, R3, R6, R7, R10, R11, R14 and R15 each independently of one another Is alkylthio group -SC _n H _{2n + 1} with n from 1 to 18. Lubricant according to claim 1, characterized in that R1 to R16 are each independently an alkylthio group with -SC _n H _{2n + 1} with n from 1 to 18. Lubricant according to Claim 1, characterized in that at least 4 of the radicals R1 to R16 are cyclohexylmethylthio -SCH ₂ C ₆ H ₁₁ . Lubricant according to one of the preceding claims, characterized in that that X represents two hydrogen atoms. Lubricant according to one of claims 1 to 4, characterized in that X Zn is. Lubricant according to claims 1 to 4, characterized in that X is Cu. Lubricant according to claims 1 to 4, characterized in that X is Ni. Lubricant according to one of the preceding claims, characterized in that that it forms a liquid-crystalline phase at normal pressure above -40 ° C. Use of a lubricant according to one of claims 1 to 9 for lubrication of plain bearings, for cold forming of metallic workpieces or for low-friction Removal of sintered metal workpieces from shaping tools. Use of a lubricant according to one of claims 1 to 8 as a fuel for internal combustion engines.